Sound absorbing structure



Sept. 5, 1933. J. MAZER 1,925,453

SOUND ABSORBING STRUCTURE Filed Dec. 22, 1928 Patented Sept. 5, 1933UNITED STATES PATENT OFFICE Application December 22, 1928 Serial No.327,968

5 Claims.

My invention relates to sound-absorbing materials and a method of makingthe same, and more particularly to materials for facing the interiors ofbuildings, and materials which not only possess desirable acoustical orsound-absorb- .ing properties, but which may also be utilized in theWalls of buildings as sound and heat insulation.

One object of my invention is to provide a material of the characterreferred to, which is of -simple and cheap construction, but which isnevertheless highly eicient.

Another object of my invention is to provide a sound-absorbing materialof such form that it may be readily applied to Walls, iloors, ceilingsand the like, which presents a smooth exposed surface and which may beconveniently painted or otherwise finished in a decorative manner.

Some of the forms which the invention may take are shown in theaccompanying drawing, wherein Figure 1 is a horizontal sectional view ofone form of wall structure in which my soundabsorbing units areemployed; Fig. 2 is a perspective view of a portion of a Wall to whichthe units are applied as in Fig. 1; Fig. 3 is a view, on an enlargedscale, of one of the units of Figs. 1 and 2, in a preliminary stage offormation; Fig. 4 is a view showing the unit of Fig. 3, crushed ordeformed to produce a desired acoustical or heat-insulating property;Fig. 5 is a composite structure involving a plurality of the units ofFig. 4 in laminated relation; Fig. 6 is a face view of the structure ofFig. 5; Fig. l shows a structure similar to Fig. l, but illustratinganother manner in which the units may be applied to a wall; and Figs. 8and 9 are modifications of the structure of Fig. 3, showing still otherforms of corrugated board from which the sound-absorbing units may beformed.

Referring more particularly to Figs. 1 to 4, 1 show a wall structurehaving an outer facing 10, studding 11, an'd sound-absorbing units 12.The units or panels 12 are nailed or otherwise suitably fastened to thestudding and have the appearance more clearly shown in Fig. 4. Theseunits are formed of what is generally designated as corrugated boardwhich may be of paper, asbestos sheets, or the like. The boardsinitially, and in their commercial form, have the appearance shown inFig. 3. A crimped or corrugated sheet 13 is suitably glued or otherwisesecured to face sheets 14 and 15. Due to the fact that only the crimpsor corrugations of sheet 13 abut the facing sheets, these are the onlypoints which are glued to the facing sheets, thereby rendering thematerial free to flex under the influence of sound waves.

I have found that by crushing the board, through pressing of the sheets14 and 15 toward one another, a very efficient sound-absorbing or c()heat-insulating unit is produced. The crushing of the board results inthe formation of a great number of grooves or recesses in the crimpedsheet 13, as compared to the fewer number of larger recesses or grooves,present in the board of Fig. 3, and also results in the elimination ofthe stiffness and comparative rigidity of the board, by reason of thefact that the truss-like effect of the corrugations is destroyed,rendering them yieldable, and the lms of glue employed for securing thesheets 13, 14 and 15 together are broken up, thus permitting the sheets14 and 15 to bend or yield under the influence of sound waves.

The yieldability of the structure after crushing results in a greatercoeicient of sound absorption. Furthermore, it can be readily handledand cut to t desired locations without affecting its acousticalproperties.

Where greater sound-absorbing capacity is desired than is possiblethrough the employment of single-layer panels, as shown in Figs. 1 and2, I will arrange a plurality of the units of Fig. 4 in laminatedrelation, as shown in Fig. 5, such laminations being held together bywire stitching 16, if desired, or they can be simply fastened to a wallstructure without being Iirst assembled as a unit.

1t will be apparent that the corrugations of adjacent composite sheetsentering into the con struction of Fig. 5 may be disposed at rightangles to one another instead of having the grooves in the sheet of eachlayer extendingparallel to the l groovesof the adjacent corrugatedsheet, thus producing a panel of greater strength and differentacoustical properties than possessed by that shown in Fig. 5.

1n Fig. 7, 1 show a structure wherein the units l2, instead of beingfastened directly to the studding, may be fastened to the faces of apartition or wall, by gluing at various points, as indicated at 17.

1n order to prevent absorption of moisture by the panel from within thewall structure, l contemplate the water-proong of either the at sheetlying next to the framework or studding, or the corrugated sheet. Itwill be understood that the inner flat sheet of paper may be omitted, ifdesired, and the corrugations bear directly against ther supportingframework. The Waterproofing may be effected by coating or impregnatingthe sheet with material having an asphalt base or other suitablewater-proofing material.

Instead of crushing the units before placing them in position upon awall, I may rst fasten the unit of the corrugated board of Fig. 3 to thewall and then crush it. This procedure results in the edges of adjacentunits being brought into snugly abutting engagement. Furthermore, theunits may be marketed as shown in Fig. 3 and may be crushed by a desiredpressure, to suit acoustical conditions or requirements at theparticular places Where they are to be employed, it being understoodthat the acoustical properties of a board crushed by a given force willbe different than if the board were crushed with a much greater force.

The degree of yieldability of the material will depend to some extentupon the sizes of the units. If a, given area is substantiallycoextensive with the exposed surface of a unit, such surface will yieldmore readily than if it merely constituted a portion of a larger unit.

In Figs. 8 and 9, I show still other forms which the corrugated board,similar to that of Fig. 3, may take. Various other modifications canobviously be made, if desired, including the omission of one sheet ofthe facing 14-15, for example.

The type of sound-absorbing structure abovedescribed lends itselfreadily to almost unlimited forms of decorativeness, either before orafter being put into place, thus making it more desirable than thosesound-absorbing materials which cannot be decorated or which can at mostbe decorated only to a, very limited extent.

recente While the term wall is employed in the appended claims, it willbe understood that the term is used in its broad sense to includeceilings, floors, columns, beams, and any other structure to which theunits may be applied.

I claim as my invention:--

l. A sound-absorbing unit having a base and a crimped sheet of yieldingmaterial carried by the base, the crimps extending laterally andirregularly from the plane of the base, at various separated points.

2. A. sound-absorbing unit comprising facing sheets and an interposedcorrugated sheet, the corrugated sheet having a major corrugated contourand being also crimped along the length of the corrugations.

3. A sound-absorbing unit comprising a body of yieldable material thathas been preformed with convex contours, and thereafter permanentlydeformed in directions toward a given plane of the body, to producecreases and crimps.

4. A sound-absorbing unit comprising a body of yieldable material thathas been preformed with convex contours, and thereafter permanentlydeformed in directions toward a given plane of the body, to producecreases and crimps, the deformed areas constituting the major portion ofone face of the unit.

5. A sound-absorbing unit comprising a plurality of layers of yieldablematerial, each layer containing creases and crimps produced bypermanently deforming preformed convex contours in directions toward agiven plane of the layer, and means for maintaining the layers inunitary relation.

JACOB MAZER.

